Peritoneal dialysis connection system and method for using ultraviolet light emitting diodes

ABSTRACT

Peritoneal dialysis systems and methods are provided by the present disclosure. In a general embodiment, a peritoneal dialysis system includes a peritoneal dialysis fluid supply, a supply line in fluid communication with the peritoneal dialysis fluid supply and terminating at a supply connector, a patient connector in fluid communication with a patient&#39;s indwelling catheter, a device configured to connect the supply connector to the patient connector without a user having to physically contact the supply connector or the patient connector, and a housing placeable around the connecting device and including a plurality of ultraviolet (“UV”) light-emitting diodes (“LED&#39;s”) positioned to direct energy towards at least one of the supply connector and the patient connector.

PRIORITY CLAIM

This application claims priority to and the benefit as a continuationapplication of U.S. patent application Ser. No. 13/468,816, filed May10, 2012, entitled, “Peritoneal Dialysis Connection System and Methodfor Using Ultraviolet Light Emitting Diodes”, which claims priority toand the benefit as a continuation application of U.S. patent applicationSer. No. 11/773,824, filed Jul. 5, 2007, entitled, “Peritoneal DialysisPatient Connection System Using Ultraviolet Light Emitting Diodes,” theentire contents of each of which are incorporated herein by referenceand relied upon.

BACKGROUND

The present disclosure relates generally to medical device connectorsand more specifically to sterilized patient connection systems forperitoneal dialysis.

Due to various causes, a person's renal system can fail. Renal failureproduces several physiological derangements. The balance of water,minerals and the excretion of daily metabolic load is no longer possibleand toxic end products of nitrogen metabolism (urea, creatinine, uricacid, and others) can accumulate in blood and tissue.

Kidney failure and reduced kidney function have been treated withdialysis. Dialysis removes waste, toxins and excess water from the bodythat would otherwise have been removed by normal functioning kidneys.Dialysis treatment for replacement of kidney functions is critical tomany people because the treatment is life saving.

One type of kidney failure therapy is peritoneal dialysis, which uses adialysis solution, also called dialysate, which is infused into apatient's peritoneal cavity via a catheter. The dialysate contacts theperitoneal membrane of the peritoneal cavity. Waste, toxins and excesswater pass from the patient's bloodstream, through the peritonealmembrane and into the dialysate due to diffusion and osmosis, i.e., anosmotic gradient occurs across the membrane. The spent dialysate isdrained from the patient, removing waste, toxins and excess water fromthe patient. This cycle is repeated.

There are various types of peritoneal dialysis therapies, includingcontinuous ambulatory peritoneal dialysis (“CAPD”), automated peritonealdialysis (“APD”), tidal flow dialysate and continuous flow peritonealdialysis (“CFPD”).

The technique of CAPD to remove impurities from the blood of a patientwhose kidneys have failed permits the patient being dialyzed to carry asurgically implanted catheter, which is generally connected(intermittently) to a peritoneal dialysis transfer set. For CAPDtreatment, the transfer set, in turn, is connected to a bag ofperitoneal dialysis solution, which is emptied through the transfer setinto the peritoneal cavity (CAPD infusion phase). For CAPD, the patientis not “tied” to a machine and can be ambulatory while the dialysisacross the peritoneal membrane (CAPD dwell phase) occurs. After thedwell phase, the peritoneal dialysis solution is drained (CAPD drainphase) from the peritoneal cavity. This can be done by allowing thesolution to flow back into the supply bag; there is preferably nodisconnection of the bag during the dwell phase. After the drain phase,the bag with spent peritoneal dialysis solution may be disconnected fromthe transfer set and discarded.

Automated peritoneal dialysis (“APD”) is similar to CAPD in that thedialysis treatment includes drain, fill, and dwell cycles. APD machinesor “cyclers”, however, perform the cycles automatically, typically whilethe patient sleeps. APD machines free patients from having to manuallyperform the treatment cycles and from having to transport suppliesduring the day. APD machines connect fluidly to an implanted catheter,to a source or bag of fresh dialysate and to a fluid drain. APD machinespump fresh dialysate from a dialysate source, through the catheter, intothe patient's peritoneal cavity, and allow the dialysate to dwell withinthe cavity, and allow the transfer of waste, toxins and excess water totake place. The source can be multiple sterile dialysate solution bags.

APD machines pump spent dialysate from the peritoneal cavity, though thecatheter, to the drain. As with the manual process, several drain, filland dwell cycles occur during dialysate. A “last fill” occurs at the endof CAPD and APD, which remains in the peritoneal cavity of the patientuntil the next treatment.

Both CAPD and APD are batch type systems that send spent dialysis fluidto a drain. Tidal flow systems are modified batch systems. With tidalflow, instead of removing all of the fluid from the patient over alonger period of time, a portion of the fluid is removed and replacedafter smaller increments of time.

Continuous flow, or CFPD, systems clean or regenerate spent dialysateinstead of discarding it. The systems pump fluid into and out of thepatient, through a loop. Dialysate flows into the peritoneal cavitythrough one catheter lumen and out another catheter lumen. The fluidexiting the patient passes through a reconstitution device that removeswaste from the dialysate, e.g., via a urea removal column that employsurease to enzymatically convert urea into ammonia. The ammonia is thenremoved from the dialysate by adsorption prior to reintroduction of thedialysate into the peritoneal cavity. Additional sensors are employed tomonitor the removal of ammonia. CFPD systems are typically morecomplicated than batch systems.

All of the above systems require the patient to connect the patient'sindwelling catheter to a PD supply apparatus via a transfer set. Thepatient connection must be kept sterile or the patient can suffer from acondition called peritonitis. The patient connection should also be easyfor the patient to make and unmake because the patient is usuallyperforming these tasks at home and/or alone. Accordingly, a need existsfor improved peritoneal dialysis patient connection systems.

SUMMARY

The present disclosure includes a system and method for connectingsupply connectors to a patient for medical systems making suchconnections. Such connections need to be made in a sterilizedenvironment in many cases so that contaminants from the supplyconnectors or from the connection process do not reach the patient. Inperitoneal dialysis for example, a catheter is implanted into thepatient's peritoneal cavity. The catheter terminates outside the bodywith a port. The port is connected to what is termed a patient transferset. The patient transfer set, in turn, is connected to a supply line,extending for example from a supply bag (typical with manual peritonealdialysis (“CAPD”)) or from a disposable cassette.

The present disclosure provides a light-emitting applicator thatsurrounds the above-described connection, so that it can be made in asterilizing environment. The applicator includes a housing, which ishinged to permit placement of a connection mechanism holding theconnectors within the light applicator. The inner surface of the housingcan have an ultraviolet (“UV”) light-reflecting material, for example,an etched aluminum coating, to maximize the exposure of ultravioletlight applied to the contents of within the applicator. The connectionmechanism is light-transmissive to allow light from the applicator toreach the connectors held by the connection mechanism.

Traditional UV light elements have used Xenon lamps. The Xenon lampshowever require a relatively high operating voltage, e.g., on the orderof hundreds of volts, to generate enough light energy. In the presentdisclosure, the light applicator includes a series of ultraviolet lightemitting diodes (“LED's”) that replace the Xenon lamp. The UV-LED's donot require the same high voltage, allowing the light applicator to bemade lighter and smaller.

The UV-LED's are spaced in an array about an inner surface of the lightapplicator, which can be at least substantially cylindrical. Asmentioned, the cylindrical housing of the light applicator is hinged inone embodiment to allow a patient assist connection device to be loadedinto the applicator. The light applicator also includes circuitry thatconnects to a power source, the circuitry operable to apply power toeach of the UV-LED's simultaneously, so that the UV-LED's collectivelysupply a proper amount of power over a period of time to effectivelydisinfect the connectors of the patient set being connected ordisconnected. The power source can be a battery source allowing forcordless operation, or an AC source, such as from a wall unit or fromthe PD cycler.

In an alternative embodiment, the power source is shifted to power theUV-LED's sequentially, e.g., full power to half of the UV-LED's for aperiod of time, then full power to the other half of the UV-LED's forthe time period, and so on over the full period of irradiation. Powercan be divided into sequential thirds or quarters and is not limited tobeing divided into halves. Further alternatively, the power source ismanipulated to switch back and forth between simultaneous and sequentialpowering over the total time as many times as desired.

In one implementation each UV-LED radiates one milli-Watt of UV energyat a peak wavelength of 280 nanometers. If 0.2 Joules/cm² of totalenergy per unit area is needed, fifty UV-LED's can be placed in an arrayon the inner surface of the housing of the light applicator to providethe needed total energy over a workable time as described in more detailbelow. The UV-LED's are capable of irradiating the transversely disposedinterior surfaces of the system, for example, the outer surface of adiaphragm initially covering a female (e.g., supply) connector, prior toits rupturing. The UV-LED's also irradiate the complex surfaces of thespike of the spike connector.

The light applicator in one embodiment includes a photocell thatmeasures the total energy of ultraviolet light applied in eachsterilization procedure. When the total energy reaches a predeterminedoverall desired exposure level, for example, about two-hundredmilliJoules per unit area (“mJ”)/cm², the photocell activates atransducer connected to the photocell to shut off the ultraviolet lightelement. The overall exposure time depends on the microbiological loadto be disinfected. Alternatively, the amount of energy required toproduce an appropriate germicidal level is determined by microbiologicalevaluation before connection, yielding a total time of exposure needed.The light applicator is then energized for the predetermined time ofexposure. Either way, the energy exposure level assures maximumantimicrobial effect on the spike and female connector.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates an embodiment of a patient assist system of thepresent disclosure.

FIG. 2 is an end view of the ultraviolet (“UV”) light-emitting diode(“LED”) applicator of the system of FIG. 1, showing the connectors forreference, and illustrating that the applicator in one embodiment ishinged.

FIG. 3 is the end view of FIG. 2 showing the applicator closed about theconnectors, such that the UV-LED's of the applicator are positioned toemit light onto the connectors from many different angles.

FIG. 4 is a side elevation view of a section taken along line IV-IV ofFIG. 3.

DETAILED DESCRIPTION

The apparatus and method discussed herein are illustrated in use with aperitoneal dialysis system, such as continuous ambulatory peritonealdialysis (“CAPD”) or an automated peritoneal dialysis (“APD”). It shouldbe appreciated however that the teachings associated with the appendeddrawings are applicable to many types of medical fluid systems. In CAPDand APD, the patient connects a supply line running to either a supplybag directly (CAPD) or to a disposable cassette (APD) operable with apumping cycler. It is important that such connection be made in asterile manner. It is also desirable to have a convenient system for thepatient, who may be ill or elderly, to operate.

The patient connects the supply line to a patient line, which can bepart of a PD transfer set, which is in turn connected to a catheterdwelling within the patient's peritoneum. The patient then has toconnect the patient line to a drain bag to enable spent dialysate to beremoved from the patient's peritoneum. The patient may have to connectmultiple supply lines, each running from a separate supply bag, to thepatient line. Between each supply bag, the patient has to connect to adrain bag. Here, it is important that the patient be able to disconnectan old supply line, connect a drain line and then connect a new supplyline readily and in a sterilizing environment.

Referring now to the drawings and in particular to FIG. 1, system 10illustrates one embodiment of a patient assist system of the presentdisclosure. FIG. 1 shows system 10 schematically and generally,highlighting the general physical and operable relationship between thecomponents. System 10 includes an ultraviolet (“UV”) light applicator20. Light applicator 20 includes a housing 22, which can be formed of aplastic or other suitable medical grade material. As shown in moredetail below, housing 22 in one embodiment is hinged so that it can fitaround a connection/disconnection device 50. A plurality of ultraviolet(“UV”) light emitting-diodes (“LED's”) 30 are placed on an inner surface24 of housing 22 of light applicator 20. UV-LED's 30 are positioned todirect energy inwardly through a body 52 of connection/disconnectiondevice 50 so as to direct disinfecting light onto a connection anddisconnection of a patient connector 80 to and from, respectively, asupply or port connector 90. Body 52 of connection/disconnection device50 is accordingly made of a UV transmissive material.

Disconnection/reconnection device 50 can have different configurationsand still operate within system 10 with UV-LED applicator 20. Onesuitable disconnection/reconnection device however is disclosed incopending U.S. patent application Ser. No. 11/773,623 (“The '623application”), filed Jul. 5, 2007, entitled “Peritoneal Dialysis PatientConnection System”, assigned to the eventual assignee of the presentapplication, the entire contents of which are incorporated herein byreference.

Patient connector 80 is connected sealingly to a patient tube 82, whichcan be part of the patient's transfer set and connect fluidly to thepatient's indwelling catheter. Supply or port connector 90 in turn isconnected to a supply line 92, which can run to either a supply bagdirectly or to a disposable cassette as described above. Port connector90 includes a pierceable diaphragm 94. Patient or spike connector 80includes or defines a spike 84, which pierces or ruptures diaphragm 94of port connector 90 when the connectors are mated. While patientconnector 80 is shown being male in nature and port connector 90 isshown being female in nature, the reverse can alternatively be true.Connectors 80 and 90 are at least partially opaque to UV light in oneembodiment.

Connection/disconnection device 50 enables connectors 80 and 90 to beconnected and disconnected without physically touching such connectorsand potentially contaminating same. Disinfecting light from UV LED's 30is radiated onto connectors 80 and 90 generally just before theconnectors are mated and just after the connectors are disconnected asshown and described in detail in the application.

Referring now to FIGS. 2 to 4, UV applicator 20 is illustrated in moredetail. FIG. 2 shows that housing 22 of UV applicator 20 is at leastsubstantially cylindrical in shape in one embodiment and includes halves26 and 28, separated by a hinge 32. Hinge 32 allows halves 26 and 28 tobe fitted about connection/disconnect device 50, which holds connectors80 and 90 shown for reference in FIGS. 2 and 3.

FIG. 3 shows halves 26 and 28 closed about connectors 80 and 90.UV-LED's 30 are positioned to radiate energy onto the connection ordisconnection of connectors 80 and 90. The at least substantiallycylindrical shape of housing 22 focuses the light from each of UV-LED's30 towards a centerline running through applicator 20, and thus towardsthe connectors. FIG. 4 is a view of the inner surface 24 of half 28 ofhousing 22 of light applicator 20, taken along line IV-IV shown in FIG.3

FIG. 4 shows that each half 26 and 28 includes a five-by-five array ofUV-LED's 30. Trace wires 36 are formed on inner surface 24 of halves 26and 28 in one embodiment to power each UV-LED 30 simultaneously, so thatthe UV-LED's 30 supply a collective amount of energy to disinfect theconnection and disconnection of connectors 80 and 90. As seen in FIG. 4,trace wires 34 terminate at power supply terminals V+ and V−. In anembodiment, a single pair of power supply terminals V+ and V− isprovided for the UV-LED's 30 of both halves 26 and 28. UV-LED's 30 canbe powered from a direct current (“DC”) source, such as an onboardreplaceable or rechargeable battery, or by an alternating currentsource, for example, via a wall outlet or from a cycler or baseinstrument.

In an alternative embodiment, software and circuitry are configured toshift the power source to power the UV-LED's 30 sequentially, e.g., fullpower to half 26 of the UV-LED's 30 for a period of time, then fullpower to the other half 28 of the UV-LED's 30 for the time period, andso on over the full period of irradiation. Full power can alternativelybe shifted sequentially between halves, thirds, quarters or otherwise asdesired. Further alternatively, the software and circuitry is configuredto manipulate the power source to switch back and forth betweensimultaneous and sequential powering of UV-LED's 30 over the total timeas many times as desired.

In an embodiment, each LED 30 operates on 0.6 Volts at 20 mA, leading toa power requirement of 120 milliWatt/per LED 30. Fifty total LED's 30would then require an overall power requirement of six Watts. This issignificantly less than the approximately forty-three Watts required bythe Xenon lamp applicator.

Inner surfaces 24 of halves 26 and 28 in one embodiment include a UVlight reflective material, for example, an etched aluminum coating,which maximizes the exposure of UV light that UV-LED's 30 impart ontoconnectors 80 and 90. The material of housing 22 is otherwise made of asuitable medical grade material, which is relatively inexpensive, suchas plastic, e.g., methacrylic resin yellow.

One suitable UV-LED 30 is provided from Seoul Semiconductor Co., Ltd,148-29 Gasan-dong Geumcheon-gu Seoul, Korea, model number S8D28D. In oneembodiment, each UV-LED 30 has a peak wavelength of about 280nanometers. Each UV-LED 30 has a power output of about one milliWatt. Ifa predetermined proper disinfection of connectors 80 and 90 requiresabout 0.2 Joules in total energy, for example, fifty UV-LED's 30 aresufficient at the above rating to supply the needed energy over asuitable time period.

The five-by-five array of UV-LED's 30 in FIG. 4 is repeated on hingedhalf 26 to provide the fifty total UV-LED's 30. In one embodiment, thefifty UV-LED's 30 are spread out evenly over halves 26 and 28 of housing22, which in one implementation has a ten mm inner diameter and forty mmlength, e.g., roughly the size of the spike 84 of connector 80. Housing22 can alternatively be larger, e.g., be large enough to encompass theconnection/disconnection device of the '623 application. The '623application discloses a hinged system in which half of theconnection/disconnection device is connected to a lid, which is hingedto a housing holding motors and other apparatuses for automaticconnection and disconnection of the connectors. In use with theconnection/disconnection device of the '623 application, halves 26 and28 would likely not be hinged to each other but instead place in theabove-mentioned lid and housing, which are in turn hinged to each other.Applicator 20 accordingly does not have to be hinged to itself Eachseparate half could have its own power supply V+ and V−, which could bepowered simultaneously to provide the needed total power. It should alsobe appreciated that in any configuration (hinged or separate), innersurfaces 24 of halves 26 and 28 can be removed for cleaning.

The combined radiation from fifty UV-LED's 30 provides a light intensityor luminance (L^(ux)) equal to (1 milliWatt×50 UV-LED's)/(10 mm×π×40mm)=4 millWatts/cm².

The UV effectiveness energy L^(ux)eff, knowing that the Xenon wavelengthis 254 nanometers (“nm”) and that a 280 nm LED has a 90% sterilizationefficiency to 254 nm light (Xenon or LED), then L^(ux)eff=4milliWatts/cm²×0.9=3.6 milliWatts/cm². Given a UV effectiveness for thefifty UV-LEDs of 3.6 milliJoules, the time required for a total energyoutput per unit area of 0.2 Joules/cm² is as follows: time ofradiation=200 milliJoules/cm²/3.6 milliWatts/cm²=56 seconds.

Another way of evaluating time of exposure, Xenon wavelength of 254 nmis used as a benchmark. That is, 200 mJ/cm² of Xenon light is sufficientfor proper disinfection. It is therefore taken that 200 mJ/cm² of 254 nmUV-LED light is also sufficient sterilization. Sterilization efficiencyof 280 nm UV-LED is 0.9×254 nm, whether UV-LED or Xenon light is used.So if 280 nm UV-LED light is used, 200 mJ/cm²/0.9=222 mJ/cm² needs to beapplied to the connector, e.g., spike connector 80. The spike 84 ofconnector 80 as discussed can be ten mm×four mm, yielding surface areaS=10 mm×π×40 mm=(4×π) cm². Fifty 280 nm LED's yield an output of 50mW=50 mJ/second. Applicator 20 can accordingly deliver 50 mW/S=50/(4×π)mJ/cm²/second. Knowing that 222 mJ is needed, fifty 280 UV-LED's willilluminate 222×(4×π)/50 in 55.8 seconds.

Fifty-six seconds of irradiation is an acceptable amount of time for thepatient when connecting or disconnecting connectors 80 and 90. Therelatively small size of UV-LED's 30 and their associated relativelysmall power requirement enables applicator 20 to made in a small,lightweight package. Further, time for irradiation should decrease LEDpower output increases. For example LED output has increased five to tentimes over the last five years.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. A peritoneal dialysis systemcomprising: a peritoneal dialysis fluid supply; a supply line in fluidcommunication with the peritoneal dialysis fluid supply, the supply lineterminating at a supply connector; a patient connector in fluidcommunication with a patient's indwelling catheter; a connecting deviceconfigured to be placed around both the supply connector and the patientconnector to connect the supply connector to the patient connectorwithout a user having to thereafter physically contact the supplyconnector or the patient connector; and a housing sized so as to beplaced about the connecting device and including a plurality ofultraviolet (“UV”) light-emitting diodes (“LED's”) positioned to directenergy towards at least one of the supply connector and the patientconnector.
 2. The peritoneal dialysis system of claim 1, wherein theplurality of UV-LED's are configured to deliver about 200 milliJoules ofenergy in a period of about a minute.
 3. The peritoneal dialysis systemof claim 1, wherein at least one of the supply connector and the patientconnector is at least partially opaque to UV light.
 4. The peritonealdialysis system of claim 1, which includes a transfer set, the transferset connecting the patient connector to the indwelling catheter.
 5. Theperitoneal dialysis system of claim 1, wherein the housing is hinged orhalved to fit around the connecting device.
 6. The peritoneal dialysissystem of claim 1, which is configured to emit UV light from theUV-LED's just prior to the supply connector and the patient connectorbeing mated via the device.
 7. The peritoneal dialysis system of claim1, which is configured to emit UV light from the UV-LED's just after thesupply connector and the patient connector are disconnected via thedevice.
 8. The peritoneal dialysis system of claim 1, wherein theperitoneal dialysis fluid supply includes a supply bag.
 9. A peritonealdialysis system comprising: a peritoneal dialysis fluid supply; a supplyline in fluid communication with the peritoneal dialysis fluid supply,the supply line terminating at a supply connector; a patient connectorin fluid communication with a patient's indwelling catheter; and aconnecting device configured to be placed around both the supplyconnector and the patient connector to connect the supply connector tothe patient connector without a user having to thereafter physicallycontact the supply connector or the patient connector; and a housingplaceable around the connecting device, the housing including aplurality of ultraviolet (“UV”) light-emitting diodes (“LED's”)positioned to direct energy towards mating surfaces of at least one ofthe supply connector and the patient connector during a connection ofthe supply connector to the patient connector.
 10. The peritonealdialysis system of claim 9, wherein the device includes a UVtransmissive material that allows the UV-LED's to direct energy inwardlythrough the device.
 11. The peritoneal dialysis system of claim 10,wherein the device allows the UV-LED's to direct energy inwardly throughthe device at a plurality of locations.
 12. The peritoneal dialysissystem of claim 9, wherein an inner surface of the housing includes a UVlight reflective material.
 13. The peritoneal dialysis system of claim9, which is configured to power a first portion of the plurality ofUV-LED's for a period of time and a second portion of the plurality ofUV-LED's after the period of time.
 14. The peritoneal dialysis system ofclaim 9, wherein the peritoneal dialysis fluid supply includes a supplybag.
 15. The peritoneal dialysis system of claim 9, wherein the UV-LED'sare positioned to direct energy towards mating surfaces of at least oneof the supply connector and the patient connector just prior to andduring the connection of the supply connector to the patient connector.16. The peritoneal dialysis system of claim 9, wherein the UV-LED's arepositioned to direct energy towards mating surfaces of at least one ofthe supply connector and the patient connector during and just afterdisconnecting the supply connector from the patient connector.